1 // SPDX-License-Identifier: GPL-1.0+ 2 /* 3 * bus driver for ccw devices 4 * 5 * Copyright IBM Corp. 2002, 2008 6 * Author(s): Arnd Bergmann (arndb@de.ibm.com) 7 * Cornelia Huck (cornelia.huck@de.ibm.com) 8 * Martin Schwidefsky (schwidefsky@de.ibm.com) 9 */ 10 11 #define KMSG_COMPONENT "cio" 12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 13 14 #include <linux/export.h> 15 #include <linux/init.h> 16 #include <linux/spinlock.h> 17 #include <linux/errno.h> 18 #include <linux/err.h> 19 #include <linux/slab.h> 20 #include <linux/list.h> 21 #include <linux/device.h> 22 #include <linux/workqueue.h> 23 #include <linux/delay.h> 24 #include <linux/timer.h> 25 #include <linux/kernel_stat.h> 26 #include <linux/sched/signal.h> 27 #include <linux/dma-mapping.h> 28 29 #include <asm/ccwdev.h> 30 #include <asm/cio.h> 31 #include <asm/param.h> /* HZ */ 32 #include <asm/cmb.h> 33 #include <asm/isc.h> 34 35 #include "chp.h" 36 #include "cio.h" 37 #include "cio_debug.h" 38 #include "css.h" 39 #include "device.h" 40 #include "ioasm.h" 41 #include "io_sch.h" 42 #include "blacklist.h" 43 #include "chsc.h" 44 45 static struct timer_list recovery_timer; 46 static DEFINE_SPINLOCK(recovery_lock); 47 static int recovery_phase; 48 static const unsigned long recovery_delay[] = { 3, 30, 300 }; 49 50 static atomic_t ccw_device_init_count = ATOMIC_INIT(0); 51 static DECLARE_WAIT_QUEUE_HEAD(ccw_device_init_wq); 52 static struct bus_type ccw_bus_type; 53 54 /******************* bus type handling ***********************/ 55 56 /* The Linux driver model distinguishes between a bus type and 57 * the bus itself. Of course we only have one channel 58 * subsystem driver and one channel system per machine, but 59 * we still use the abstraction. T.R. says it's a good idea. */ 60 static int 61 ccw_bus_match (struct device * dev, struct device_driver * drv) 62 { 63 struct ccw_device *cdev = to_ccwdev(dev); 64 struct ccw_driver *cdrv = to_ccwdrv(drv); 65 const struct ccw_device_id *ids = cdrv->ids, *found; 66 67 if (!ids) 68 return 0; 69 70 found = ccw_device_id_match(ids, &cdev->id); 71 if (!found) 72 return 0; 73 74 cdev->id.driver_info = found->driver_info; 75 76 return 1; 77 } 78 79 /* Store modalias string delimited by prefix/suffix string into buffer with 80 * specified size. Return length of resulting string (excluding trailing '\0') 81 * even if string doesn't fit buffer (snprintf semantics). */ 82 static int snprint_alias(char *buf, size_t size, 83 struct ccw_device_id *id, const char *suffix) 84 { 85 int len; 86 87 len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model); 88 if (len > size) 89 return len; 90 buf += len; 91 size -= len; 92 93 if (id->dev_type != 0) 94 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type, 95 id->dev_model, suffix); 96 else 97 len += snprintf(buf, size, "dtdm%s", suffix); 98 99 return len; 100 } 101 102 /* Set up environment variables for ccw device uevent. Return 0 on success, 103 * non-zero otherwise. */ 104 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env) 105 { 106 struct ccw_device *cdev = to_ccwdev(dev); 107 struct ccw_device_id *id = &(cdev->id); 108 int ret; 109 char modalias_buf[30]; 110 111 /* CU_TYPE= */ 112 ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type); 113 if (ret) 114 return ret; 115 116 /* CU_MODEL= */ 117 ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model); 118 if (ret) 119 return ret; 120 121 /* The next two can be zero, that's ok for us */ 122 /* DEV_TYPE= */ 123 ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type); 124 if (ret) 125 return ret; 126 127 /* DEV_MODEL= */ 128 ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model); 129 if (ret) 130 return ret; 131 132 /* MODALIAS= */ 133 snprint_alias(modalias_buf, sizeof(modalias_buf), id, ""); 134 ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf); 135 return ret; 136 } 137 138 static void io_subchannel_irq(struct subchannel *); 139 static int io_subchannel_probe(struct subchannel *); 140 static int io_subchannel_remove(struct subchannel *); 141 static void io_subchannel_shutdown(struct subchannel *); 142 static int io_subchannel_sch_event(struct subchannel *, int); 143 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *, 144 int); 145 static void recovery_func(struct timer_list *unused); 146 147 static struct css_device_id io_subchannel_ids[] = { 148 { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, }, 149 { /* end of list */ }, 150 }; 151 152 static int io_subchannel_settle(void) 153 { 154 int ret; 155 156 ret = wait_event_interruptible(ccw_device_init_wq, 157 atomic_read(&ccw_device_init_count) == 0); 158 if (ret) 159 return -EINTR; 160 flush_workqueue(cio_work_q); 161 return 0; 162 } 163 164 static struct css_driver io_subchannel_driver = { 165 .drv = { 166 .owner = THIS_MODULE, 167 .name = "io_subchannel", 168 }, 169 .subchannel_type = io_subchannel_ids, 170 .irq = io_subchannel_irq, 171 .sch_event = io_subchannel_sch_event, 172 .chp_event = io_subchannel_chp_event, 173 .probe = io_subchannel_probe, 174 .remove = io_subchannel_remove, 175 .shutdown = io_subchannel_shutdown, 176 .settle = io_subchannel_settle, 177 }; 178 179 int __init io_subchannel_init(void) 180 { 181 int ret; 182 183 timer_setup(&recovery_timer, recovery_func, 0); 184 ret = bus_register(&ccw_bus_type); 185 if (ret) 186 return ret; 187 ret = css_driver_register(&io_subchannel_driver); 188 if (ret) 189 bus_unregister(&ccw_bus_type); 190 191 return ret; 192 } 193 194 195 /************************ device handling **************************/ 196 197 static ssize_t 198 devtype_show (struct device *dev, struct device_attribute *attr, char *buf) 199 { 200 struct ccw_device *cdev = to_ccwdev(dev); 201 struct ccw_device_id *id = &(cdev->id); 202 203 if (id->dev_type != 0) 204 return sprintf(buf, "%04x/%02x\n", 205 id->dev_type, id->dev_model); 206 else 207 return sprintf(buf, "n/a\n"); 208 } 209 210 static ssize_t 211 cutype_show (struct device *dev, struct device_attribute *attr, char *buf) 212 { 213 struct ccw_device *cdev = to_ccwdev(dev); 214 struct ccw_device_id *id = &(cdev->id); 215 216 return sprintf(buf, "%04x/%02x\n", 217 id->cu_type, id->cu_model); 218 } 219 220 static ssize_t 221 modalias_show (struct device *dev, struct device_attribute *attr, char *buf) 222 { 223 struct ccw_device *cdev = to_ccwdev(dev); 224 struct ccw_device_id *id = &(cdev->id); 225 int len; 226 227 len = snprint_alias(buf, PAGE_SIZE, id, "\n"); 228 229 return len > PAGE_SIZE ? PAGE_SIZE : len; 230 } 231 232 static ssize_t 233 online_show (struct device *dev, struct device_attribute *attr, char *buf) 234 { 235 struct ccw_device *cdev = to_ccwdev(dev); 236 237 return sprintf(buf, cdev->online ? "1\n" : "0\n"); 238 } 239 240 int ccw_device_is_orphan(struct ccw_device *cdev) 241 { 242 return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent)); 243 } 244 245 static void ccw_device_unregister(struct ccw_device *cdev) 246 { 247 if (device_is_registered(&cdev->dev)) { 248 /* Undo device_add(). */ 249 device_del(&cdev->dev); 250 } 251 if (cdev->private->flags.initialized) { 252 cdev->private->flags.initialized = 0; 253 /* Release reference from device_initialize(). */ 254 put_device(&cdev->dev); 255 } 256 } 257 258 static void io_subchannel_quiesce(struct subchannel *); 259 260 /** 261 * ccw_device_set_offline() - disable a ccw device for I/O 262 * @cdev: target ccw device 263 * 264 * This function calls the driver's set_offline() function for @cdev, if 265 * given, and then disables @cdev. 266 * Returns: 267 * %0 on success and a negative error value on failure. 268 * Context: 269 * enabled, ccw device lock not held 270 */ 271 int ccw_device_set_offline(struct ccw_device *cdev) 272 { 273 struct subchannel *sch; 274 int ret, state; 275 276 if (!cdev) 277 return -ENODEV; 278 if (!cdev->online || !cdev->drv) 279 return -EINVAL; 280 281 if (cdev->drv->set_offline) { 282 ret = cdev->drv->set_offline(cdev); 283 if (ret != 0) 284 return ret; 285 } 286 spin_lock_irq(cdev->ccwlock); 287 sch = to_subchannel(cdev->dev.parent); 288 cdev->online = 0; 289 /* Wait until a final state or DISCONNECTED is reached */ 290 while (!dev_fsm_final_state(cdev) && 291 cdev->private->state != DEV_STATE_DISCONNECTED) { 292 spin_unlock_irq(cdev->ccwlock); 293 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) || 294 cdev->private->state == DEV_STATE_DISCONNECTED)); 295 spin_lock_irq(cdev->ccwlock); 296 } 297 do { 298 ret = ccw_device_offline(cdev); 299 if (!ret) 300 break; 301 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device " 302 "0.%x.%04x\n", ret, cdev->private->dev_id.ssid, 303 cdev->private->dev_id.devno); 304 if (ret != -EBUSY) 305 goto error; 306 state = cdev->private->state; 307 spin_unlock_irq(cdev->ccwlock); 308 io_subchannel_quiesce(sch); 309 spin_lock_irq(cdev->ccwlock); 310 cdev->private->state = state; 311 } while (ret == -EBUSY); 312 spin_unlock_irq(cdev->ccwlock); 313 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) || 314 cdev->private->state == DEV_STATE_DISCONNECTED)); 315 /* Inform the user if set offline failed. */ 316 if (cdev->private->state == DEV_STATE_BOXED) { 317 pr_warn("%s: The device entered boxed state while being set offline\n", 318 dev_name(&cdev->dev)); 319 } else if (cdev->private->state == DEV_STATE_NOT_OPER) { 320 pr_warn("%s: The device stopped operating while being set offline\n", 321 dev_name(&cdev->dev)); 322 } 323 /* Give up reference from ccw_device_set_online(). */ 324 put_device(&cdev->dev); 325 return 0; 326 327 error: 328 cdev->private->state = DEV_STATE_OFFLINE; 329 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 330 spin_unlock_irq(cdev->ccwlock); 331 /* Give up reference from ccw_device_set_online(). */ 332 put_device(&cdev->dev); 333 return -ENODEV; 334 } 335 336 /** 337 * ccw_device_set_online() - enable a ccw device for I/O 338 * @cdev: target ccw device 339 * 340 * This function first enables @cdev and then calls the driver's set_online() 341 * function for @cdev, if given. If set_online() returns an error, @cdev is 342 * disabled again. 343 * Returns: 344 * %0 on success and a negative error value on failure. 345 * Context: 346 * enabled, ccw device lock not held 347 */ 348 int ccw_device_set_online(struct ccw_device *cdev) 349 { 350 int ret; 351 int ret2; 352 353 if (!cdev) 354 return -ENODEV; 355 if (cdev->online || !cdev->drv) 356 return -EINVAL; 357 /* Hold on to an extra reference while device is online. */ 358 if (!get_device(&cdev->dev)) 359 return -ENODEV; 360 361 spin_lock_irq(cdev->ccwlock); 362 ret = ccw_device_online(cdev); 363 spin_unlock_irq(cdev->ccwlock); 364 if (ret == 0) 365 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev)); 366 else { 367 CIO_MSG_EVENT(0, "ccw_device_online returned %d, " 368 "device 0.%x.%04x\n", 369 ret, cdev->private->dev_id.ssid, 370 cdev->private->dev_id.devno); 371 /* Give up online reference since onlining failed. */ 372 put_device(&cdev->dev); 373 return ret; 374 } 375 spin_lock_irq(cdev->ccwlock); 376 /* Check if online processing was successful */ 377 if ((cdev->private->state != DEV_STATE_ONLINE) && 378 (cdev->private->state != DEV_STATE_W4SENSE)) { 379 spin_unlock_irq(cdev->ccwlock); 380 /* Inform the user that set online failed. */ 381 if (cdev->private->state == DEV_STATE_BOXED) { 382 pr_warn("%s: Setting the device online failed because it is boxed\n", 383 dev_name(&cdev->dev)); 384 } else if (cdev->private->state == DEV_STATE_NOT_OPER) { 385 pr_warn("%s: Setting the device online failed because it is not operational\n", 386 dev_name(&cdev->dev)); 387 } 388 /* Give up online reference since onlining failed. */ 389 put_device(&cdev->dev); 390 return -ENODEV; 391 } 392 spin_unlock_irq(cdev->ccwlock); 393 if (cdev->drv->set_online) 394 ret = cdev->drv->set_online(cdev); 395 if (ret) 396 goto rollback; 397 398 spin_lock_irq(cdev->ccwlock); 399 cdev->online = 1; 400 spin_unlock_irq(cdev->ccwlock); 401 return 0; 402 403 rollback: 404 spin_lock_irq(cdev->ccwlock); 405 /* Wait until a final state or DISCONNECTED is reached */ 406 while (!dev_fsm_final_state(cdev) && 407 cdev->private->state != DEV_STATE_DISCONNECTED) { 408 spin_unlock_irq(cdev->ccwlock); 409 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) || 410 cdev->private->state == DEV_STATE_DISCONNECTED)); 411 spin_lock_irq(cdev->ccwlock); 412 } 413 ret2 = ccw_device_offline(cdev); 414 if (ret2) 415 goto error; 416 spin_unlock_irq(cdev->ccwlock); 417 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) || 418 cdev->private->state == DEV_STATE_DISCONNECTED)); 419 /* Give up online reference since onlining failed. */ 420 put_device(&cdev->dev); 421 return ret; 422 423 error: 424 CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, " 425 "device 0.%x.%04x\n", 426 ret2, cdev->private->dev_id.ssid, 427 cdev->private->dev_id.devno); 428 cdev->private->state = DEV_STATE_OFFLINE; 429 spin_unlock_irq(cdev->ccwlock); 430 /* Give up online reference since onlining failed. */ 431 put_device(&cdev->dev); 432 return ret; 433 } 434 435 static int online_store_handle_offline(struct ccw_device *cdev) 436 { 437 if (cdev->private->state == DEV_STATE_DISCONNECTED) { 438 spin_lock_irq(cdev->ccwlock); 439 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL); 440 spin_unlock_irq(cdev->ccwlock); 441 return 0; 442 } 443 if (cdev->drv && cdev->drv->set_offline) 444 return ccw_device_set_offline(cdev); 445 return -EINVAL; 446 } 447 448 static int online_store_recog_and_online(struct ccw_device *cdev) 449 { 450 /* Do device recognition, if needed. */ 451 if (cdev->private->state == DEV_STATE_BOXED) { 452 spin_lock_irq(cdev->ccwlock); 453 ccw_device_recognition(cdev); 454 spin_unlock_irq(cdev->ccwlock); 455 wait_event(cdev->private->wait_q, 456 cdev->private->flags.recog_done); 457 if (cdev->private->state != DEV_STATE_OFFLINE) 458 /* recognition failed */ 459 return -EAGAIN; 460 } 461 if (cdev->drv && cdev->drv->set_online) 462 return ccw_device_set_online(cdev); 463 return -EINVAL; 464 } 465 466 static int online_store_handle_online(struct ccw_device *cdev, int force) 467 { 468 int ret; 469 470 ret = online_store_recog_and_online(cdev); 471 if (ret && !force) 472 return ret; 473 if (force && cdev->private->state == DEV_STATE_BOXED) { 474 ret = ccw_device_stlck(cdev); 475 if (ret) 476 return ret; 477 if (cdev->id.cu_type == 0) 478 cdev->private->state = DEV_STATE_NOT_OPER; 479 ret = online_store_recog_and_online(cdev); 480 if (ret) 481 return ret; 482 } 483 return 0; 484 } 485 486 static ssize_t online_store (struct device *dev, struct device_attribute *attr, 487 const char *buf, size_t count) 488 { 489 struct ccw_device *cdev = to_ccwdev(dev); 490 int force, ret; 491 unsigned long i; 492 493 /* Prevent conflict between multiple on-/offline processing requests. */ 494 if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0) 495 return -EAGAIN; 496 /* Prevent conflict between internal I/Os and on-/offline processing. */ 497 if (!dev_fsm_final_state(cdev) && 498 cdev->private->state != DEV_STATE_DISCONNECTED) { 499 ret = -EAGAIN; 500 goto out; 501 } 502 /* Prevent conflict between pending work and on-/offline processing.*/ 503 if (work_pending(&cdev->private->todo_work)) { 504 ret = -EAGAIN; 505 goto out; 506 } 507 if (!strncmp(buf, "force\n", count)) { 508 force = 1; 509 i = 1; 510 ret = 0; 511 } else { 512 force = 0; 513 ret = kstrtoul(buf, 16, &i); 514 } 515 if (ret) 516 goto out; 517 518 device_lock(dev); 519 switch (i) { 520 case 0: 521 ret = online_store_handle_offline(cdev); 522 break; 523 case 1: 524 ret = online_store_handle_online(cdev, force); 525 break; 526 default: 527 ret = -EINVAL; 528 } 529 device_unlock(dev); 530 531 out: 532 atomic_set(&cdev->private->onoff, 0); 533 return (ret < 0) ? ret : count; 534 } 535 536 static ssize_t 537 available_show (struct device *dev, struct device_attribute *attr, char *buf) 538 { 539 struct ccw_device *cdev = to_ccwdev(dev); 540 struct subchannel *sch; 541 542 if (ccw_device_is_orphan(cdev)) 543 return sprintf(buf, "no device\n"); 544 switch (cdev->private->state) { 545 case DEV_STATE_BOXED: 546 return sprintf(buf, "boxed\n"); 547 case DEV_STATE_DISCONNECTED: 548 case DEV_STATE_DISCONNECTED_SENSE_ID: 549 case DEV_STATE_NOT_OPER: 550 sch = to_subchannel(dev->parent); 551 if (!sch->lpm) 552 return sprintf(buf, "no path\n"); 553 else 554 return sprintf(buf, "no device\n"); 555 default: 556 /* All other states considered fine. */ 557 return sprintf(buf, "good\n"); 558 } 559 } 560 561 static ssize_t 562 initiate_logging(struct device *dev, struct device_attribute *attr, 563 const char *buf, size_t count) 564 { 565 struct subchannel *sch = to_subchannel(dev); 566 int rc; 567 568 rc = chsc_siosl(sch->schid); 569 if (rc < 0) { 570 pr_warn("Logging for subchannel 0.%x.%04x failed with errno=%d\n", 571 sch->schid.ssid, sch->schid.sch_no, rc); 572 return rc; 573 } 574 pr_notice("Logging for subchannel 0.%x.%04x was triggered\n", 575 sch->schid.ssid, sch->schid.sch_no); 576 return count; 577 } 578 579 static ssize_t vpm_show(struct device *dev, struct device_attribute *attr, 580 char *buf) 581 { 582 struct subchannel *sch = to_subchannel(dev); 583 584 return sprintf(buf, "%02x\n", sch->vpm); 585 } 586 587 static DEVICE_ATTR_RO(devtype); 588 static DEVICE_ATTR_RO(cutype); 589 static DEVICE_ATTR_RO(modalias); 590 static DEVICE_ATTR_RW(online); 591 static DEVICE_ATTR(availability, 0444, available_show, NULL); 592 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging); 593 static DEVICE_ATTR_RO(vpm); 594 595 static struct attribute *io_subchannel_attrs[] = { 596 &dev_attr_logging.attr, 597 &dev_attr_vpm.attr, 598 NULL, 599 }; 600 601 static const struct attribute_group io_subchannel_attr_group = { 602 .attrs = io_subchannel_attrs, 603 }; 604 605 static struct attribute * ccwdev_attrs[] = { 606 &dev_attr_devtype.attr, 607 &dev_attr_cutype.attr, 608 &dev_attr_modalias.attr, 609 &dev_attr_online.attr, 610 &dev_attr_cmb_enable.attr, 611 &dev_attr_availability.attr, 612 NULL, 613 }; 614 615 static const struct attribute_group ccwdev_attr_group = { 616 .attrs = ccwdev_attrs, 617 }; 618 619 static const struct attribute_group *ccwdev_attr_groups[] = { 620 &ccwdev_attr_group, 621 NULL, 622 }; 623 624 static int match_dev_id(struct device *dev, const void *data) 625 { 626 struct ccw_device *cdev = to_ccwdev(dev); 627 struct ccw_dev_id *dev_id = (void *)data; 628 629 return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id); 630 } 631 632 /** 633 * get_ccwdev_by_dev_id() - obtain device from a ccw device id 634 * @dev_id: id of the device to be searched 635 * 636 * This function searches all devices attached to the ccw bus for a device 637 * matching @dev_id. 638 * Returns: 639 * If a device is found its reference count is increased and returned; 640 * else %NULL is returned. 641 */ 642 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id) 643 { 644 struct device *dev; 645 646 dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id); 647 648 return dev ? to_ccwdev(dev) : NULL; 649 } 650 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id); 651 652 static void ccw_device_do_unbind_bind(struct ccw_device *cdev) 653 { 654 int ret; 655 656 if (device_is_registered(&cdev->dev)) { 657 device_release_driver(&cdev->dev); 658 ret = device_attach(&cdev->dev); 659 WARN_ON(ret == -ENODEV); 660 } 661 } 662 663 static void 664 ccw_device_release(struct device *dev) 665 { 666 struct ccw_device *cdev; 667 668 cdev = to_ccwdev(dev); 669 cio_gp_dma_free(cdev->private->dma_pool, cdev->private->dma_area, 670 sizeof(*cdev->private->dma_area)); 671 cio_gp_dma_destroy(cdev->private->dma_pool, &cdev->dev); 672 /* Release reference of parent subchannel. */ 673 put_device(cdev->dev.parent); 674 kfree(cdev->private); 675 kfree(cdev); 676 } 677 678 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch) 679 { 680 struct ccw_device *cdev; 681 struct gen_pool *dma_pool; 682 int ret; 683 684 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL); 685 if (!cdev) { 686 ret = -ENOMEM; 687 goto err_cdev; 688 } 689 cdev->private = kzalloc(sizeof(struct ccw_device_private), 690 GFP_KERNEL | GFP_DMA); 691 if (!cdev->private) { 692 ret = -ENOMEM; 693 goto err_priv; 694 } 695 696 cdev->dev.dma_mask = sch->dev.dma_mask; 697 ret = dma_set_coherent_mask(&cdev->dev, sch->dev.coherent_dma_mask); 698 if (ret) 699 goto err_coherent_mask; 700 701 dma_pool = cio_gp_dma_create(&cdev->dev, 1); 702 if (!dma_pool) { 703 ret = -ENOMEM; 704 goto err_dma_pool; 705 } 706 cdev->private->dma_pool = dma_pool; 707 cdev->private->dma_area = cio_gp_dma_zalloc(dma_pool, &cdev->dev, 708 sizeof(*cdev->private->dma_area)); 709 if (!cdev->private->dma_area) { 710 ret = -ENOMEM; 711 goto err_dma_area; 712 } 713 return cdev; 714 err_dma_area: 715 cio_gp_dma_destroy(dma_pool, &cdev->dev); 716 err_dma_pool: 717 err_coherent_mask: 718 kfree(cdev->private); 719 err_priv: 720 kfree(cdev); 721 err_cdev: 722 return ERR_PTR(ret); 723 } 724 725 static void ccw_device_todo(struct work_struct *work); 726 727 static int io_subchannel_initialize_dev(struct subchannel *sch, 728 struct ccw_device *cdev) 729 { 730 struct ccw_device_private *priv = cdev->private; 731 int ret; 732 733 priv->cdev = cdev; 734 priv->int_class = IRQIO_CIO; 735 priv->state = DEV_STATE_NOT_OPER; 736 priv->dev_id.devno = sch->schib.pmcw.dev; 737 priv->dev_id.ssid = sch->schid.ssid; 738 739 INIT_WORK(&priv->todo_work, ccw_device_todo); 740 INIT_LIST_HEAD(&priv->cmb_list); 741 init_waitqueue_head(&priv->wait_q); 742 timer_setup(&priv->timer, ccw_device_timeout, 0); 743 744 atomic_set(&priv->onoff, 0); 745 cdev->ccwlock = sch->lock; 746 cdev->dev.parent = &sch->dev; 747 cdev->dev.release = ccw_device_release; 748 cdev->dev.bus = &ccw_bus_type; 749 cdev->dev.groups = ccwdev_attr_groups; 750 /* Do first half of device_register. */ 751 device_initialize(&cdev->dev); 752 ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid, 753 cdev->private->dev_id.devno); 754 if (ret) 755 goto out_put; 756 if (!get_device(&sch->dev)) { 757 ret = -ENODEV; 758 goto out_put; 759 } 760 priv->flags.initialized = 1; 761 spin_lock_irq(sch->lock); 762 sch_set_cdev(sch, cdev); 763 spin_unlock_irq(sch->lock); 764 return 0; 765 766 out_put: 767 /* Release reference from device_initialize(). */ 768 put_device(&cdev->dev); 769 return ret; 770 } 771 772 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch) 773 { 774 struct ccw_device *cdev; 775 int ret; 776 777 cdev = io_subchannel_allocate_dev(sch); 778 if (!IS_ERR(cdev)) { 779 ret = io_subchannel_initialize_dev(sch, cdev); 780 if (ret) 781 cdev = ERR_PTR(ret); 782 } 783 return cdev; 784 } 785 786 static void io_subchannel_recog(struct ccw_device *, struct subchannel *); 787 788 static void sch_create_and_recog_new_device(struct subchannel *sch) 789 { 790 struct ccw_device *cdev; 791 792 /* Need to allocate a new ccw device. */ 793 cdev = io_subchannel_create_ccwdev(sch); 794 if (IS_ERR(cdev)) { 795 /* OK, we did everything we could... */ 796 css_sch_device_unregister(sch); 797 return; 798 } 799 /* Start recognition for the new ccw device. */ 800 io_subchannel_recog(cdev, sch); 801 } 802 803 /* 804 * Register recognized device. 805 */ 806 static void io_subchannel_register(struct ccw_device *cdev) 807 { 808 struct subchannel *sch; 809 int ret, adjust_init_count = 1; 810 unsigned long flags; 811 812 sch = to_subchannel(cdev->dev.parent); 813 /* 814 * Check if subchannel is still registered. It may have become 815 * unregistered if a machine check hit us after finishing 816 * device recognition but before the register work could be 817 * queued. 818 */ 819 if (!device_is_registered(&sch->dev)) 820 goto out_err; 821 css_update_ssd_info(sch); 822 /* 823 * io_subchannel_register() will also be called after device 824 * recognition has been done for a boxed device (which will already 825 * be registered). We need to reprobe since we may now have sense id 826 * information. 827 */ 828 if (device_is_registered(&cdev->dev)) { 829 if (!cdev->drv) { 830 ret = device_reprobe(&cdev->dev); 831 if (ret) 832 /* We can't do much here. */ 833 CIO_MSG_EVENT(0, "device_reprobe() returned" 834 " %d for 0.%x.%04x\n", ret, 835 cdev->private->dev_id.ssid, 836 cdev->private->dev_id.devno); 837 } 838 adjust_init_count = 0; 839 goto out; 840 } 841 /* 842 * Now we know this subchannel will stay, we can throw 843 * our delayed uevent. 844 */ 845 if (dev_get_uevent_suppress(&sch->dev)) { 846 dev_set_uevent_suppress(&sch->dev, 0); 847 kobject_uevent(&sch->dev.kobj, KOBJ_ADD); 848 } 849 /* make it known to the system */ 850 ret = device_add(&cdev->dev); 851 if (ret) { 852 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n", 853 cdev->private->dev_id.ssid, 854 cdev->private->dev_id.devno, ret); 855 spin_lock_irqsave(sch->lock, flags); 856 sch_set_cdev(sch, NULL); 857 spin_unlock_irqrestore(sch->lock, flags); 858 /* Release initial device reference. */ 859 put_device(&cdev->dev); 860 goto out_err; 861 } 862 out: 863 cdev->private->flags.recog_done = 1; 864 wake_up(&cdev->private->wait_q); 865 out_err: 866 if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count)) 867 wake_up(&ccw_device_init_wq); 868 } 869 870 static void ccw_device_call_sch_unregister(struct ccw_device *cdev) 871 { 872 struct subchannel *sch; 873 874 /* Get subchannel reference for local processing. */ 875 if (!get_device(cdev->dev.parent)) 876 return; 877 sch = to_subchannel(cdev->dev.parent); 878 css_sch_device_unregister(sch); 879 /* Release subchannel reference for local processing. */ 880 put_device(&sch->dev); 881 } 882 883 /* 884 * subchannel recognition done. Called from the state machine. 885 */ 886 void 887 io_subchannel_recog_done(struct ccw_device *cdev) 888 { 889 if (css_init_done == 0) { 890 cdev->private->flags.recog_done = 1; 891 return; 892 } 893 switch (cdev->private->state) { 894 case DEV_STATE_BOXED: 895 /* Device did not respond in time. */ 896 case DEV_STATE_NOT_OPER: 897 cdev->private->flags.recog_done = 1; 898 /* Remove device found not operational. */ 899 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 900 if (atomic_dec_and_test(&ccw_device_init_count)) 901 wake_up(&ccw_device_init_wq); 902 break; 903 case DEV_STATE_OFFLINE: 904 /* 905 * We can't register the device in interrupt context so 906 * we schedule a work item. 907 */ 908 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER); 909 break; 910 } 911 } 912 913 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch) 914 { 915 /* Increase counter of devices currently in recognition. */ 916 atomic_inc(&ccw_device_init_count); 917 918 /* Start async. device sensing. */ 919 spin_lock_irq(sch->lock); 920 ccw_device_recognition(cdev); 921 spin_unlock_irq(sch->lock); 922 } 923 924 static int ccw_device_move_to_sch(struct ccw_device *cdev, 925 struct subchannel *sch) 926 { 927 struct subchannel *old_sch; 928 int rc, old_enabled = 0; 929 930 old_sch = to_subchannel(cdev->dev.parent); 931 /* Obtain child reference for new parent. */ 932 if (!get_device(&sch->dev)) 933 return -ENODEV; 934 935 if (!sch_is_pseudo_sch(old_sch)) { 936 spin_lock_irq(old_sch->lock); 937 old_enabled = old_sch->schib.pmcw.ena; 938 rc = 0; 939 if (old_enabled) 940 rc = cio_disable_subchannel(old_sch); 941 spin_unlock_irq(old_sch->lock); 942 if (rc == -EBUSY) { 943 /* Release child reference for new parent. */ 944 put_device(&sch->dev); 945 return rc; 946 } 947 } 948 949 mutex_lock(&sch->reg_mutex); 950 rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV); 951 mutex_unlock(&sch->reg_mutex); 952 if (rc) { 953 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n", 954 cdev->private->dev_id.ssid, 955 cdev->private->dev_id.devno, sch->schid.ssid, 956 sch->schib.pmcw.dev, rc); 957 if (old_enabled) { 958 /* Try to reenable the old subchannel. */ 959 spin_lock_irq(old_sch->lock); 960 cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch); 961 spin_unlock_irq(old_sch->lock); 962 } 963 /* Release child reference for new parent. */ 964 put_device(&sch->dev); 965 return rc; 966 } 967 /* Clean up old subchannel. */ 968 if (!sch_is_pseudo_sch(old_sch)) { 969 spin_lock_irq(old_sch->lock); 970 sch_set_cdev(old_sch, NULL); 971 spin_unlock_irq(old_sch->lock); 972 css_schedule_eval(old_sch->schid); 973 } 974 /* Release child reference for old parent. */ 975 put_device(&old_sch->dev); 976 /* Initialize new subchannel. */ 977 spin_lock_irq(sch->lock); 978 cdev->ccwlock = sch->lock; 979 if (!sch_is_pseudo_sch(sch)) 980 sch_set_cdev(sch, cdev); 981 spin_unlock_irq(sch->lock); 982 if (!sch_is_pseudo_sch(sch)) 983 css_update_ssd_info(sch); 984 return 0; 985 } 986 987 static int ccw_device_move_to_orph(struct ccw_device *cdev) 988 { 989 struct subchannel *sch = to_subchannel(cdev->dev.parent); 990 struct channel_subsystem *css = to_css(sch->dev.parent); 991 992 return ccw_device_move_to_sch(cdev, css->pseudo_subchannel); 993 } 994 995 static void io_subchannel_irq(struct subchannel *sch) 996 { 997 struct ccw_device *cdev; 998 999 cdev = sch_get_cdev(sch); 1000 1001 CIO_TRACE_EVENT(6, "IRQ"); 1002 CIO_TRACE_EVENT(6, dev_name(&sch->dev)); 1003 if (cdev) 1004 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT); 1005 else 1006 inc_irq_stat(IRQIO_CIO); 1007 } 1008 1009 void io_subchannel_init_config(struct subchannel *sch) 1010 { 1011 memset(&sch->config, 0, sizeof(sch->config)); 1012 sch->config.csense = 1; 1013 } 1014 1015 static void io_subchannel_init_fields(struct subchannel *sch) 1016 { 1017 if (cio_is_console(sch->schid)) 1018 sch->opm = 0xff; 1019 else 1020 sch->opm = chp_get_sch_opm(sch); 1021 sch->lpm = sch->schib.pmcw.pam & sch->opm; 1022 sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC; 1023 1024 CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X" 1025 " - PIM = %02X, PAM = %02X, POM = %02X\n", 1026 sch->schib.pmcw.dev, sch->schid.ssid, 1027 sch->schid.sch_no, sch->schib.pmcw.pim, 1028 sch->schib.pmcw.pam, sch->schib.pmcw.pom); 1029 1030 io_subchannel_init_config(sch); 1031 } 1032 1033 /* 1034 * Note: We always return 0 so that we bind to the device even on error. 1035 * This is needed so that our remove function is called on unregister. 1036 */ 1037 static int io_subchannel_probe(struct subchannel *sch) 1038 { 1039 struct io_subchannel_private *io_priv; 1040 struct ccw_device *cdev; 1041 int rc; 1042 1043 if (cio_is_console(sch->schid)) { 1044 rc = sysfs_create_group(&sch->dev.kobj, 1045 &io_subchannel_attr_group); 1046 if (rc) 1047 CIO_MSG_EVENT(0, "Failed to create io subchannel " 1048 "attributes for subchannel " 1049 "0.%x.%04x (rc=%d)\n", 1050 sch->schid.ssid, sch->schid.sch_no, rc); 1051 /* 1052 * The console subchannel already has an associated ccw_device. 1053 * Throw the delayed uevent for the subchannel, register 1054 * the ccw_device and exit. 1055 */ 1056 if (dev_get_uevent_suppress(&sch->dev)) { 1057 /* should always be the case for the console */ 1058 dev_set_uevent_suppress(&sch->dev, 0); 1059 kobject_uevent(&sch->dev.kobj, KOBJ_ADD); 1060 } 1061 cdev = sch_get_cdev(sch); 1062 rc = device_add(&cdev->dev); 1063 if (rc) { 1064 /* Release online reference. */ 1065 put_device(&cdev->dev); 1066 goto out_schedule; 1067 } 1068 if (atomic_dec_and_test(&ccw_device_init_count)) 1069 wake_up(&ccw_device_init_wq); 1070 return 0; 1071 } 1072 io_subchannel_init_fields(sch); 1073 rc = cio_commit_config(sch); 1074 if (rc) 1075 goto out_schedule; 1076 rc = sysfs_create_group(&sch->dev.kobj, 1077 &io_subchannel_attr_group); 1078 if (rc) 1079 goto out_schedule; 1080 /* Allocate I/O subchannel private data. */ 1081 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA); 1082 if (!io_priv) 1083 goto out_schedule; 1084 1085 io_priv->dma_area = dma_alloc_coherent(&sch->dev, 1086 sizeof(*io_priv->dma_area), 1087 &io_priv->dma_area_dma, GFP_KERNEL); 1088 if (!io_priv->dma_area) { 1089 kfree(io_priv); 1090 goto out_schedule; 1091 } 1092 1093 set_io_private(sch, io_priv); 1094 css_schedule_eval(sch->schid); 1095 return 0; 1096 1097 out_schedule: 1098 spin_lock_irq(sch->lock); 1099 css_sched_sch_todo(sch, SCH_TODO_UNREG); 1100 spin_unlock_irq(sch->lock); 1101 return 0; 1102 } 1103 1104 static int io_subchannel_remove(struct subchannel *sch) 1105 { 1106 struct io_subchannel_private *io_priv = to_io_private(sch); 1107 struct ccw_device *cdev; 1108 1109 cdev = sch_get_cdev(sch); 1110 if (!cdev) 1111 goto out_free; 1112 1113 ccw_device_unregister(cdev); 1114 spin_lock_irq(sch->lock); 1115 sch_set_cdev(sch, NULL); 1116 set_io_private(sch, NULL); 1117 spin_unlock_irq(sch->lock); 1118 out_free: 1119 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1120 io_priv->dma_area, io_priv->dma_area_dma); 1121 kfree(io_priv); 1122 sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group); 1123 return 0; 1124 } 1125 1126 static void io_subchannel_verify(struct subchannel *sch) 1127 { 1128 struct ccw_device *cdev; 1129 1130 cdev = sch_get_cdev(sch); 1131 if (cdev) 1132 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1133 } 1134 1135 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask) 1136 { 1137 struct ccw_device *cdev; 1138 1139 cdev = sch_get_cdev(sch); 1140 if (!cdev) 1141 return; 1142 if (cio_update_schib(sch)) 1143 goto err; 1144 /* Check for I/O on path. */ 1145 if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask) 1146 goto out; 1147 if (cdev->private->state == DEV_STATE_ONLINE) { 1148 ccw_device_kill_io(cdev); 1149 goto out; 1150 } 1151 if (cio_clear(sch)) 1152 goto err; 1153 out: 1154 /* Trigger path verification. */ 1155 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1156 return; 1157 1158 err: 1159 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 1160 } 1161 1162 static int io_subchannel_chp_event(struct subchannel *sch, 1163 struct chp_link *link, int event) 1164 { 1165 struct ccw_device *cdev = sch_get_cdev(sch); 1166 int mask, chpid, valid_bit; 1167 int path_event[8]; 1168 1169 mask = chp_ssd_get_mask(&sch->ssd_info, link); 1170 if (!mask) 1171 return 0; 1172 switch (event) { 1173 case CHP_VARY_OFF: 1174 sch->opm &= ~mask; 1175 sch->lpm &= ~mask; 1176 if (cdev) 1177 cdev->private->path_gone_mask |= mask; 1178 io_subchannel_terminate_path(sch, mask); 1179 break; 1180 case CHP_VARY_ON: 1181 sch->opm |= mask; 1182 sch->lpm |= mask; 1183 if (cdev) 1184 cdev->private->path_new_mask |= mask; 1185 io_subchannel_verify(sch); 1186 break; 1187 case CHP_OFFLINE: 1188 if (cio_update_schib(sch)) 1189 return -ENODEV; 1190 if (cdev) 1191 cdev->private->path_gone_mask |= mask; 1192 io_subchannel_terminate_path(sch, mask); 1193 break; 1194 case CHP_ONLINE: 1195 if (cio_update_schib(sch)) 1196 return -ENODEV; 1197 sch->lpm |= mask & sch->opm; 1198 if (cdev) 1199 cdev->private->path_new_mask |= mask; 1200 io_subchannel_verify(sch); 1201 break; 1202 case CHP_FCES_EVENT: 1203 /* Forward Endpoint Security event */ 1204 for (chpid = 0, valid_bit = 0x80; chpid < 8; chpid++, 1205 valid_bit >>= 1) { 1206 if (mask & valid_bit) 1207 path_event[chpid] = PE_PATH_FCES_EVENT; 1208 else 1209 path_event[chpid] = PE_NONE; 1210 } 1211 if (cdev) 1212 cdev->drv->path_event(cdev, path_event); 1213 break; 1214 } 1215 return 0; 1216 } 1217 1218 static void io_subchannel_quiesce(struct subchannel *sch) 1219 { 1220 struct ccw_device *cdev; 1221 int ret; 1222 1223 spin_lock_irq(sch->lock); 1224 cdev = sch_get_cdev(sch); 1225 if (cio_is_console(sch->schid)) 1226 goto out_unlock; 1227 if (!sch->schib.pmcw.ena) 1228 goto out_unlock; 1229 ret = cio_disable_subchannel(sch); 1230 if (ret != -EBUSY) 1231 goto out_unlock; 1232 if (cdev->handler) 1233 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO)); 1234 while (ret == -EBUSY) { 1235 cdev->private->state = DEV_STATE_QUIESCE; 1236 cdev->private->iretry = 255; 1237 ret = ccw_device_cancel_halt_clear(cdev); 1238 if (ret == -EBUSY) { 1239 ccw_device_set_timeout(cdev, HZ/10); 1240 spin_unlock_irq(sch->lock); 1241 wait_event(cdev->private->wait_q, 1242 cdev->private->state != DEV_STATE_QUIESCE); 1243 spin_lock_irq(sch->lock); 1244 } 1245 ret = cio_disable_subchannel(sch); 1246 } 1247 out_unlock: 1248 spin_unlock_irq(sch->lock); 1249 } 1250 1251 static void io_subchannel_shutdown(struct subchannel *sch) 1252 { 1253 io_subchannel_quiesce(sch); 1254 } 1255 1256 static int device_is_disconnected(struct ccw_device *cdev) 1257 { 1258 if (!cdev) 1259 return 0; 1260 return (cdev->private->state == DEV_STATE_DISCONNECTED || 1261 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID); 1262 } 1263 1264 static int recovery_check(struct device *dev, void *data) 1265 { 1266 struct ccw_device *cdev = to_ccwdev(dev); 1267 struct subchannel *sch; 1268 int *redo = data; 1269 1270 spin_lock_irq(cdev->ccwlock); 1271 switch (cdev->private->state) { 1272 case DEV_STATE_ONLINE: 1273 sch = to_subchannel(cdev->dev.parent); 1274 if ((sch->schib.pmcw.pam & sch->opm) == sch->vpm) 1275 break; 1276 fallthrough; 1277 case DEV_STATE_DISCONNECTED: 1278 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n", 1279 cdev->private->dev_id.ssid, 1280 cdev->private->dev_id.devno); 1281 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1282 *redo = 1; 1283 break; 1284 case DEV_STATE_DISCONNECTED_SENSE_ID: 1285 *redo = 1; 1286 break; 1287 } 1288 spin_unlock_irq(cdev->ccwlock); 1289 1290 return 0; 1291 } 1292 1293 static void recovery_work_func(struct work_struct *unused) 1294 { 1295 int redo = 0; 1296 1297 bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check); 1298 if (redo) { 1299 spin_lock_irq(&recovery_lock); 1300 if (!timer_pending(&recovery_timer)) { 1301 if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1) 1302 recovery_phase++; 1303 mod_timer(&recovery_timer, jiffies + 1304 recovery_delay[recovery_phase] * HZ); 1305 } 1306 spin_unlock_irq(&recovery_lock); 1307 } else 1308 CIO_MSG_EVENT(3, "recovery: end\n"); 1309 } 1310 1311 static DECLARE_WORK(recovery_work, recovery_work_func); 1312 1313 static void recovery_func(struct timer_list *unused) 1314 { 1315 /* 1316 * We can't do our recovery in softirq context and it's not 1317 * performance critical, so we schedule it. 1318 */ 1319 schedule_work(&recovery_work); 1320 } 1321 1322 void ccw_device_schedule_recovery(void) 1323 { 1324 unsigned long flags; 1325 1326 CIO_MSG_EVENT(3, "recovery: schedule\n"); 1327 spin_lock_irqsave(&recovery_lock, flags); 1328 if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) { 1329 recovery_phase = 0; 1330 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ); 1331 } 1332 spin_unlock_irqrestore(&recovery_lock, flags); 1333 } 1334 1335 static int purge_fn(struct device *dev, void *data) 1336 { 1337 struct ccw_device *cdev = to_ccwdev(dev); 1338 struct ccw_dev_id *id = &cdev->private->dev_id; 1339 1340 spin_lock_irq(cdev->ccwlock); 1341 if (is_blacklisted(id->ssid, id->devno) && 1342 (cdev->private->state == DEV_STATE_OFFLINE) && 1343 (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) { 1344 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid, 1345 id->devno); 1346 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 1347 atomic_set(&cdev->private->onoff, 0); 1348 } 1349 spin_unlock_irq(cdev->ccwlock); 1350 /* Abort loop in case of pending signal. */ 1351 if (signal_pending(current)) 1352 return -EINTR; 1353 1354 return 0; 1355 } 1356 1357 /** 1358 * ccw_purge_blacklisted - purge unused, blacklisted devices 1359 * 1360 * Unregister all ccw devices that are offline and on the blacklist. 1361 */ 1362 int ccw_purge_blacklisted(void) 1363 { 1364 CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n"); 1365 bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn); 1366 return 0; 1367 } 1368 1369 void ccw_device_set_disconnected(struct ccw_device *cdev) 1370 { 1371 if (!cdev) 1372 return; 1373 ccw_device_set_timeout(cdev, 0); 1374 cdev->private->flags.fake_irb = 0; 1375 cdev->private->state = DEV_STATE_DISCONNECTED; 1376 if (cdev->online) 1377 ccw_device_schedule_recovery(); 1378 } 1379 1380 void ccw_device_set_notoper(struct ccw_device *cdev) 1381 { 1382 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1383 1384 CIO_TRACE_EVENT(2, "notoper"); 1385 CIO_TRACE_EVENT(2, dev_name(&sch->dev)); 1386 ccw_device_set_timeout(cdev, 0); 1387 cio_disable_subchannel(sch); 1388 cdev->private->state = DEV_STATE_NOT_OPER; 1389 } 1390 1391 enum io_sch_action { 1392 IO_SCH_UNREG, 1393 IO_SCH_ORPH_UNREG, 1394 IO_SCH_ATTACH, 1395 IO_SCH_UNREG_ATTACH, 1396 IO_SCH_ORPH_ATTACH, 1397 IO_SCH_REPROBE, 1398 IO_SCH_VERIFY, 1399 IO_SCH_DISC, 1400 IO_SCH_NOP, 1401 }; 1402 1403 static enum io_sch_action sch_get_action(struct subchannel *sch) 1404 { 1405 struct ccw_device *cdev; 1406 1407 cdev = sch_get_cdev(sch); 1408 if (cio_update_schib(sch)) { 1409 /* Not operational. */ 1410 if (!cdev) 1411 return IO_SCH_UNREG; 1412 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 1413 return IO_SCH_UNREG; 1414 return IO_SCH_ORPH_UNREG; 1415 } 1416 /* Operational. */ 1417 if (!cdev) 1418 return IO_SCH_ATTACH; 1419 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) { 1420 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 1421 return IO_SCH_UNREG_ATTACH; 1422 return IO_SCH_ORPH_ATTACH; 1423 } 1424 if ((sch->schib.pmcw.pam & sch->opm) == 0) { 1425 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) 1426 return IO_SCH_UNREG; 1427 return IO_SCH_DISC; 1428 } 1429 if (device_is_disconnected(cdev)) 1430 return IO_SCH_REPROBE; 1431 if (cdev->online) 1432 return IO_SCH_VERIFY; 1433 if (cdev->private->state == DEV_STATE_NOT_OPER) 1434 return IO_SCH_UNREG_ATTACH; 1435 return IO_SCH_NOP; 1436 } 1437 1438 /** 1439 * io_subchannel_sch_event - process subchannel event 1440 * @sch: subchannel 1441 * @process: non-zero if function is called in process context 1442 * 1443 * An unspecified event occurred for this subchannel. Adjust data according 1444 * to the current operational state of the subchannel and device. Return 1445 * zero when the event has been handled sufficiently or -EAGAIN when this 1446 * function should be called again in process context. 1447 */ 1448 static int io_subchannel_sch_event(struct subchannel *sch, int process) 1449 { 1450 unsigned long flags; 1451 struct ccw_device *cdev; 1452 struct ccw_dev_id dev_id; 1453 enum io_sch_action action; 1454 int rc = -EAGAIN; 1455 1456 spin_lock_irqsave(sch->lock, flags); 1457 if (!device_is_registered(&sch->dev)) 1458 goto out_unlock; 1459 if (work_pending(&sch->todo_work)) 1460 goto out_unlock; 1461 cdev = sch_get_cdev(sch); 1462 if (cdev && work_pending(&cdev->private->todo_work)) 1463 goto out_unlock; 1464 action = sch_get_action(sch); 1465 CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n", 1466 sch->schid.ssid, sch->schid.sch_no, process, 1467 action); 1468 /* Perform immediate actions while holding the lock. */ 1469 switch (action) { 1470 case IO_SCH_REPROBE: 1471 /* Trigger device recognition. */ 1472 ccw_device_trigger_reprobe(cdev); 1473 rc = 0; 1474 goto out_unlock; 1475 case IO_SCH_VERIFY: 1476 /* Trigger path verification. */ 1477 io_subchannel_verify(sch); 1478 rc = 0; 1479 goto out_unlock; 1480 case IO_SCH_DISC: 1481 ccw_device_set_disconnected(cdev); 1482 rc = 0; 1483 goto out_unlock; 1484 case IO_SCH_ORPH_UNREG: 1485 case IO_SCH_ORPH_ATTACH: 1486 ccw_device_set_disconnected(cdev); 1487 break; 1488 case IO_SCH_UNREG_ATTACH: 1489 case IO_SCH_UNREG: 1490 if (!cdev) 1491 break; 1492 if (cdev->private->state == DEV_STATE_SENSE_ID) { 1493 /* 1494 * Note: delayed work triggered by this event 1495 * and repeated calls to sch_event are synchronized 1496 * by the above check for work_pending(cdev). 1497 */ 1498 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 1499 } else 1500 ccw_device_set_notoper(cdev); 1501 break; 1502 case IO_SCH_NOP: 1503 rc = 0; 1504 goto out_unlock; 1505 default: 1506 break; 1507 } 1508 spin_unlock_irqrestore(sch->lock, flags); 1509 /* All other actions require process context. */ 1510 if (!process) 1511 goto out; 1512 /* Handle attached ccw device. */ 1513 switch (action) { 1514 case IO_SCH_ORPH_UNREG: 1515 case IO_SCH_ORPH_ATTACH: 1516 /* Move ccw device to orphanage. */ 1517 rc = ccw_device_move_to_orph(cdev); 1518 if (rc) 1519 goto out; 1520 break; 1521 case IO_SCH_UNREG_ATTACH: 1522 spin_lock_irqsave(sch->lock, flags); 1523 sch_set_cdev(sch, NULL); 1524 spin_unlock_irqrestore(sch->lock, flags); 1525 /* Unregister ccw device. */ 1526 ccw_device_unregister(cdev); 1527 break; 1528 default: 1529 break; 1530 } 1531 /* Handle subchannel. */ 1532 switch (action) { 1533 case IO_SCH_ORPH_UNREG: 1534 case IO_SCH_UNREG: 1535 if (!cdev) 1536 css_sch_device_unregister(sch); 1537 break; 1538 case IO_SCH_ORPH_ATTACH: 1539 case IO_SCH_UNREG_ATTACH: 1540 case IO_SCH_ATTACH: 1541 dev_id.ssid = sch->schid.ssid; 1542 dev_id.devno = sch->schib.pmcw.dev; 1543 cdev = get_ccwdev_by_dev_id(&dev_id); 1544 if (!cdev) { 1545 sch_create_and_recog_new_device(sch); 1546 break; 1547 } 1548 rc = ccw_device_move_to_sch(cdev, sch); 1549 if (rc) { 1550 /* Release reference from get_ccwdev_by_dev_id() */ 1551 put_device(&cdev->dev); 1552 goto out; 1553 } 1554 spin_lock_irqsave(sch->lock, flags); 1555 ccw_device_trigger_reprobe(cdev); 1556 spin_unlock_irqrestore(sch->lock, flags); 1557 /* Release reference from get_ccwdev_by_dev_id() */ 1558 put_device(&cdev->dev); 1559 break; 1560 default: 1561 break; 1562 } 1563 return 0; 1564 1565 out_unlock: 1566 spin_unlock_irqrestore(sch->lock, flags); 1567 out: 1568 return rc; 1569 } 1570 1571 static void ccw_device_set_int_class(struct ccw_device *cdev) 1572 { 1573 struct ccw_driver *cdrv = cdev->drv; 1574 1575 /* Note: we interpret class 0 in this context as an uninitialized 1576 * field since it translates to a non-I/O interrupt class. */ 1577 if (cdrv->int_class != 0) 1578 cdev->private->int_class = cdrv->int_class; 1579 else 1580 cdev->private->int_class = IRQIO_CIO; 1581 } 1582 1583 #ifdef CONFIG_CCW_CONSOLE 1584 int __init ccw_device_enable_console(struct ccw_device *cdev) 1585 { 1586 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1587 int rc; 1588 1589 if (!cdev->drv || !cdev->handler) 1590 return -EINVAL; 1591 1592 io_subchannel_init_fields(sch); 1593 rc = cio_commit_config(sch); 1594 if (rc) 1595 return rc; 1596 sch->driver = &io_subchannel_driver; 1597 io_subchannel_recog(cdev, sch); 1598 /* Now wait for the async. recognition to come to an end. */ 1599 spin_lock_irq(cdev->ccwlock); 1600 while (!dev_fsm_final_state(cdev)) 1601 ccw_device_wait_idle(cdev); 1602 1603 /* Hold on to an extra reference while device is online. */ 1604 get_device(&cdev->dev); 1605 rc = ccw_device_online(cdev); 1606 if (rc) 1607 goto out_unlock; 1608 1609 while (!dev_fsm_final_state(cdev)) 1610 ccw_device_wait_idle(cdev); 1611 1612 if (cdev->private->state == DEV_STATE_ONLINE) 1613 cdev->online = 1; 1614 else 1615 rc = -EIO; 1616 out_unlock: 1617 spin_unlock_irq(cdev->ccwlock); 1618 if (rc) /* Give up online reference since onlining failed. */ 1619 put_device(&cdev->dev); 1620 return rc; 1621 } 1622 1623 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv) 1624 { 1625 struct io_subchannel_private *io_priv; 1626 struct ccw_device *cdev; 1627 struct subchannel *sch; 1628 1629 sch = cio_probe_console(); 1630 if (IS_ERR(sch)) 1631 return ERR_CAST(sch); 1632 1633 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA); 1634 if (!io_priv) 1635 goto err_priv; 1636 io_priv->dma_area = dma_alloc_coherent(&sch->dev, 1637 sizeof(*io_priv->dma_area), 1638 &io_priv->dma_area_dma, GFP_KERNEL); 1639 if (!io_priv->dma_area) 1640 goto err_dma_area; 1641 set_io_private(sch, io_priv); 1642 cdev = io_subchannel_create_ccwdev(sch); 1643 if (IS_ERR(cdev)) { 1644 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1645 io_priv->dma_area, io_priv->dma_area_dma); 1646 set_io_private(sch, NULL); 1647 put_device(&sch->dev); 1648 kfree(io_priv); 1649 return cdev; 1650 } 1651 cdev->drv = drv; 1652 ccw_device_set_int_class(cdev); 1653 return cdev; 1654 1655 err_dma_area: 1656 kfree(io_priv); 1657 err_priv: 1658 put_device(&sch->dev); 1659 return ERR_PTR(-ENOMEM); 1660 } 1661 1662 void __init ccw_device_destroy_console(struct ccw_device *cdev) 1663 { 1664 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1665 struct io_subchannel_private *io_priv = to_io_private(sch); 1666 1667 set_io_private(sch, NULL); 1668 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1669 io_priv->dma_area, io_priv->dma_area_dma); 1670 put_device(&sch->dev); 1671 put_device(&cdev->dev); 1672 kfree(io_priv); 1673 } 1674 1675 /** 1676 * ccw_device_wait_idle() - busy wait for device to become idle 1677 * @cdev: ccw device 1678 * 1679 * Poll until activity control is zero, that is, no function or data 1680 * transfer is pending/active. 1681 * Called with device lock being held. 1682 */ 1683 void ccw_device_wait_idle(struct ccw_device *cdev) 1684 { 1685 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1686 1687 while (1) { 1688 cio_tsch(sch); 1689 if (sch->schib.scsw.cmd.actl == 0) 1690 break; 1691 udelay(100); 1692 } 1693 } 1694 #endif 1695 1696 /** 1697 * get_ccwdev_by_busid() - obtain device from a bus id 1698 * @cdrv: driver the device is owned by 1699 * @bus_id: bus id of the device to be searched 1700 * 1701 * This function searches all devices owned by @cdrv for a device with a bus 1702 * id matching @bus_id. 1703 * Returns: 1704 * If a match is found, its reference count of the found device is increased 1705 * and it is returned; else %NULL is returned. 1706 */ 1707 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv, 1708 const char *bus_id) 1709 { 1710 struct device *dev; 1711 1712 dev = driver_find_device_by_name(&cdrv->driver, bus_id); 1713 1714 return dev ? to_ccwdev(dev) : NULL; 1715 } 1716 1717 /************************** device driver handling ************************/ 1718 1719 /* This is the implementation of the ccw_driver class. The probe, remove 1720 * and release methods are initially very similar to the device_driver 1721 * implementations, with the difference that they have ccw_device 1722 * arguments. 1723 * 1724 * A ccw driver also contains the information that is needed for 1725 * device matching. 1726 */ 1727 static int 1728 ccw_device_probe (struct device *dev) 1729 { 1730 struct ccw_device *cdev = to_ccwdev(dev); 1731 struct ccw_driver *cdrv = to_ccwdrv(dev->driver); 1732 int ret; 1733 1734 cdev->drv = cdrv; /* to let the driver call _set_online */ 1735 ccw_device_set_int_class(cdev); 1736 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV; 1737 if (ret) { 1738 cdev->drv = NULL; 1739 cdev->private->int_class = IRQIO_CIO; 1740 return ret; 1741 } 1742 1743 return 0; 1744 } 1745 1746 static int ccw_device_remove(struct device *dev) 1747 { 1748 struct ccw_device *cdev = to_ccwdev(dev); 1749 struct ccw_driver *cdrv = cdev->drv; 1750 struct subchannel *sch; 1751 int ret; 1752 1753 if (cdrv->remove) 1754 cdrv->remove(cdev); 1755 1756 spin_lock_irq(cdev->ccwlock); 1757 if (cdev->online) { 1758 cdev->online = 0; 1759 ret = ccw_device_offline(cdev); 1760 spin_unlock_irq(cdev->ccwlock); 1761 if (ret == 0) 1762 wait_event(cdev->private->wait_q, 1763 dev_fsm_final_state(cdev)); 1764 else 1765 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, " 1766 "device 0.%x.%04x\n", 1767 ret, cdev->private->dev_id.ssid, 1768 cdev->private->dev_id.devno); 1769 /* Give up reference obtained in ccw_device_set_online(). */ 1770 put_device(&cdev->dev); 1771 spin_lock_irq(cdev->ccwlock); 1772 } 1773 ccw_device_set_timeout(cdev, 0); 1774 cdev->drv = NULL; 1775 cdev->private->int_class = IRQIO_CIO; 1776 sch = to_subchannel(cdev->dev.parent); 1777 spin_unlock_irq(cdev->ccwlock); 1778 io_subchannel_quiesce(sch); 1779 __disable_cmf(cdev); 1780 1781 return 0; 1782 } 1783 1784 static void ccw_device_shutdown(struct device *dev) 1785 { 1786 struct ccw_device *cdev; 1787 1788 cdev = to_ccwdev(dev); 1789 if (cdev->drv && cdev->drv->shutdown) 1790 cdev->drv->shutdown(cdev); 1791 __disable_cmf(cdev); 1792 } 1793 1794 static struct bus_type ccw_bus_type = { 1795 .name = "ccw", 1796 .match = ccw_bus_match, 1797 .uevent = ccw_uevent, 1798 .probe = ccw_device_probe, 1799 .remove = ccw_device_remove, 1800 .shutdown = ccw_device_shutdown, 1801 }; 1802 1803 /** 1804 * ccw_driver_register() - register a ccw driver 1805 * @cdriver: driver to be registered 1806 * 1807 * This function is mainly a wrapper around driver_register(). 1808 * Returns: 1809 * %0 on success and a negative error value on failure. 1810 */ 1811 int ccw_driver_register(struct ccw_driver *cdriver) 1812 { 1813 struct device_driver *drv = &cdriver->driver; 1814 1815 drv->bus = &ccw_bus_type; 1816 1817 return driver_register(drv); 1818 } 1819 1820 /** 1821 * ccw_driver_unregister() - deregister a ccw driver 1822 * @cdriver: driver to be deregistered 1823 * 1824 * This function is mainly a wrapper around driver_unregister(). 1825 */ 1826 void ccw_driver_unregister(struct ccw_driver *cdriver) 1827 { 1828 driver_unregister(&cdriver->driver); 1829 } 1830 1831 static void ccw_device_todo(struct work_struct *work) 1832 { 1833 struct ccw_device_private *priv; 1834 struct ccw_device *cdev; 1835 struct subchannel *sch; 1836 enum cdev_todo todo; 1837 1838 priv = container_of(work, struct ccw_device_private, todo_work); 1839 cdev = priv->cdev; 1840 sch = to_subchannel(cdev->dev.parent); 1841 /* Find out todo. */ 1842 spin_lock_irq(cdev->ccwlock); 1843 todo = priv->todo; 1844 priv->todo = CDEV_TODO_NOTHING; 1845 CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n", 1846 priv->dev_id.ssid, priv->dev_id.devno, todo); 1847 spin_unlock_irq(cdev->ccwlock); 1848 /* Perform todo. */ 1849 switch (todo) { 1850 case CDEV_TODO_ENABLE_CMF: 1851 cmf_reenable(cdev); 1852 break; 1853 case CDEV_TODO_REBIND: 1854 ccw_device_do_unbind_bind(cdev); 1855 break; 1856 case CDEV_TODO_REGISTER: 1857 io_subchannel_register(cdev); 1858 break; 1859 case CDEV_TODO_UNREG_EVAL: 1860 if (!sch_is_pseudo_sch(sch)) 1861 css_schedule_eval(sch->schid); 1862 fallthrough; 1863 case CDEV_TODO_UNREG: 1864 if (sch_is_pseudo_sch(sch)) 1865 ccw_device_unregister(cdev); 1866 else 1867 ccw_device_call_sch_unregister(cdev); 1868 break; 1869 default: 1870 break; 1871 } 1872 /* Release workqueue ref. */ 1873 put_device(&cdev->dev); 1874 } 1875 1876 /** 1877 * ccw_device_sched_todo - schedule ccw device operation 1878 * @cdev: ccw device 1879 * @todo: todo 1880 * 1881 * Schedule the operation identified by @todo to be performed on the slow path 1882 * workqueue. Do nothing if another operation with higher priority is already 1883 * scheduled. Needs to be called with ccwdev lock held. 1884 */ 1885 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo) 1886 { 1887 CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n", 1888 cdev->private->dev_id.ssid, cdev->private->dev_id.devno, 1889 todo); 1890 if (cdev->private->todo >= todo) 1891 return; 1892 cdev->private->todo = todo; 1893 /* Get workqueue ref. */ 1894 if (!get_device(&cdev->dev)) 1895 return; 1896 if (!queue_work(cio_work_q, &cdev->private->todo_work)) { 1897 /* Already queued, release workqueue ref. */ 1898 put_device(&cdev->dev); 1899 } 1900 } 1901 1902 /** 1903 * ccw_device_siosl() - initiate logging 1904 * @cdev: ccw device 1905 * 1906 * This function is used to invoke model-dependent logging within the channel 1907 * subsystem. 1908 */ 1909 int ccw_device_siosl(struct ccw_device *cdev) 1910 { 1911 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1912 1913 return chsc_siosl(sch->schid); 1914 } 1915 EXPORT_SYMBOL_GPL(ccw_device_siosl); 1916 1917 EXPORT_SYMBOL(ccw_device_set_online); 1918 EXPORT_SYMBOL(ccw_device_set_offline); 1919 EXPORT_SYMBOL(ccw_driver_register); 1920 EXPORT_SYMBOL(ccw_driver_unregister); 1921 EXPORT_SYMBOL(get_ccwdev_by_busid); 1922